<quiz shuffle=none display=simple>
{Select the statement that shows the sum of population of all countries in 'Europe'
|type="()"}
- SELECT name, population FROM bbc WHERE region = 'Europe'
- SELECT population FROM bbc WHERE region = 'Europe' SUM BY region
+ SELECT SUM(population) FROM bbc WHERE region = 'Europe'
- SELECT SUM(population FROM bbc WHERE region = 'Europe')
- SUM population FROM bbc WHERE region = 'Europe'

{Select the statement that shows the number of countries with population smaller than 150000
|type="()"}
+ SELECT COUNT(name) FROM bbc WHERE population < 150000
- SELECT COUNT(population < 150000) FROM bbc
- SELECT name FROM bbc WHERE population < 150000
- SELECT population AS COUNT FROM bbc WHERE population < 150000
- SELECT SUM() FROM bbc WHERE population < 150000

{Select the statement that shows the average population of 'Poland', 'Germany' and 'Denmark'
|type="()"}
-A. SELECT AVG(population) FROM bbc WHERE name = ('Poland', 'Germany', 'Denmark')
+B. SELECT AVG(population) FROM bbc WHERE name IN ('Poland', 'Germany', 'Denmark')
-C. SELECT AVG(population) FROM bbc WHERE name LIKE ('Poland', 'Germany', 'Denmark')
-D. SELECT AVG(population) FROM bbc WHERE name LIKE (Poland, Germany, Denmark)
-E. SELECT population FROM bbc WHERE name IN ('Poland', 'Germany', 'Denmark')

{Select the statement that shows the medium population density of each region
|type="()"}
-A. SELECT region, AVG(population/area) AS density FROM bbc
-B. SELECT region, COUNT(population)/COUNT(area) AS density FROM bbc GROUP BY region
-C. SELECT region, SUM(population)/COUNT(area) AS density FROM bbc GROUP BY region
-D. SELECT region, SUM(population)/SUM(area) AS density FROM bbc HAVING region
+E. SELECT region, SUM(population)/SUM(area) AS density FROM bbc GROUP BY region

{Select the statement that shows the name and population density of the country with the largest population
|type="()"}
-A. SELECT name, density AS population/area FROM bbc WHERE population = MAX(population)
-B. SELECT name, density AS population/area FROM bbc WHERE population = (SELECT MAX(population) FROM bbc)
-C. SELECT name, MAX (population) FROM bbc WHERE population / (SELECT area FROM bbc)
+D. SELECT name, population/area AS density FROM bbc WHERE population = (SELECT MAX(population) FROM bbc)
-E. SELECT name, population/area AS density FROM bbc WHERE population > (SELECT MAX(population) FROM bbc)